Does NS120 support SMB3 in latest dart version?

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Celerra Support Forum

No the latest version of DART for the Celerra (v6.0.70.4 as of this writing) does not include support for SMB3.  In anticipation of your follow-up question, as for whether or not it will be backported, please reach out to your account team.

Currently SMB3 support is only available with VNX OE for File v7.1 on Windows 8 client and Windows Server 2012 client.